He told them they must not be swayed by public opinion or by the Clarks not testifying in their own defence.

"The death of John Clark is a tragic loss, but his death in and of itself does not mean that a criminal offence must have been committed," Jeffrey told jurors.

"If you conclude Jennifer Clark or Jeromie Clark are not guilty of a criminal offence, it does not mean you agree with their decisions or actions or that you condone some or all of their possible choices. It is only a statement of whether they committed a criminal offence."

The Crown argued John was on the verge of death when he arrived in hospital on November 28, 2013, and that his parents played with his life by not seeking treatment sooner.

Jurors were shown pictures of John after he died. He had blackened toes and a red rash that covered almost three-quarters of his body. The forensic pathologist's report said John was malnourished and died from a staph infection.

The Clarks' lawyers say doctors at the Alberta Children's Hospital were to blame because they raised the boy's sodium and fluid levels too aggressively.

The trial heard John died the day after he was brought to hospital, where he had a seizure and two cardiac arrests.

David Stephan, who with his wife Collet are to be tried a second time next spring in the 2012 death of their son, sat in the gallery with a notebook during the Clarks' trial. He was not present Thursday for the jury instructions.

The Stephans were found guilty in 2016 of failing to provide the necessaries of life to 19-month-old Ezekiel, who died from meningitis.

Their trial in Lethbridge, Alta., heard evidence that they treated the boy with garlic, onion and horseradish rather than take him to a doctor. The Stephans eventually called 911 but the toddler died in hospital.

In May, the Supreme Court of Canada ordered a new trial for the Stephans, saying the judge did not properly instruct jurors on what would be a marked departure from reasonable behaviour "in a way that the jury could understand and apply."

In a Facebook video from outside the courthouse on Tuesday, Stephan said even if the Clarks win, justice will not be served until the doctors who cared for him are held accountable.

"All it's doing is preventing further injustices from taking place. All it's doing is preventing the dirty pharmaceutical agenda from spreading at a greater rate," he said.

"All it's doing is hopefully preventing parents from engaging unnecessary treatments, unnecessary vaccinations because they're not terrified of going to jail like Jennifer and Jeromie Clark did or like David and Collet Stephan did."